Railcar for passenger transport

ABSTRACT

This railcar is of the type comprising: 
     carriages including two driving carriages and intermediate carriages; 
     carrier bogies, motor bogies comprising at least one motor axle; 
     traction drives which are capable of supplying electrical energy to the motors of the motor bogies. 
     According to one feature of the invention, all the carriages have passenger compartments, the railcar is completely articulated, the traction drives are arranged in three carriages and a motor bogie is arranged below at least one end of each carriage which receives a traction drive.

TECHNICAL FIELD

The present invention relates to a railcar for passenger transport andmore specifically a railcar which can be adjusted in terms of passengercapacity and in terms of maximum speed.

BACKGROUND TO THE INVENTION

The architectures of trains or railcars are differentiated depending onwhether they have concentrated or distributed motorisation, depending onwhether the carriages composing them are connected in an articulated ornon-articulated manner, depending on the arrangement and the number ofmotor and carrier bogies, and depending on whether they are single ordouble deck.

For reasons of clarity, these various notions are defined in thefollowing paragraphs.

Train or Railcar

A railcar comprises at least one motorised carriage, that is to say,comprising at least one passenger compartment and at least one tractiondrive. A railcar may thus comprise only motorised carriages or comprisenon-motorised carriages and at least one motorised carriage.

A train is composed of one or more motor cars and a specific number ofpassenger carriages. A motor car is not accessible to passengers andcomprises, inter alia, a traction drive.

Concentrated or Distributed Motorisation

The traction drive comprises a plurality of items of equipment which areeither electrical components or electronic power and control componentswhich are capable of acquiring the electrical energy from a tractionsource (for example, a catenary line), transforming it and converting itinto electrical signals for supplying electric motors of the motorbogies in order to drive the train or the railcar.

The motorisation is said to be concentrated when all the components ofthe traction drives are grouped in a single location, for example, inthe motor car of a train. The motorisation is said to be distributedwhen the components of the traction drive are distributed over aplurality of carriages, below the chassis of the carriages or in theroof.

Articulated Carriages or Non-Articulated Carriages

A bogie conventionally comprises a bogie chassis which rests on twoaxles. The term axle is generally intended to refer to a pair of coaxialwheels which rest on the rails of a rail track.

A motor bogie comprises at least one electrical motor for driving thewheels of at least one of the axles thereof, referred to as a motoraxle. In contrast, a non-motorised bogie is referred to as a carrierbogie.

Two adjacent carriages are said to be “articulated” (or in a state ofarticulated connection) when a first carriage is supported with one ofthe ends thereof on a bogie and the end facing the second carriage restson the end of the first one. The bogie therefore straddles below theends of the two adjacent carriages. A railcar which is composed of twoarticulated carriages therefore comprises three bogies, since the freeends of the two carriages each rest on a bogie.

In contrast, two non-articulated adjacent carriages are not, at each ofthe ends thereof, supported on a common bogie, each carriage resting ontwo bogies. A railcar composed of two non-articulated carriagestherefore comprises four bogies.

Single or Double Deck Carriage

A carriage is said to be single deck when it has a passenger compartmenton a single floor level and it is said to be double deck when itcomprises two passenger compartments on two levels, superimposed oneabove the other.

There are single deck trains, which are non-articulated and which havemotorisation concentrated in one or two motor cars. Owing to thenon-articulation, this architecture has the disadvantage of having alarge number of bogies which increases the resistance to forwardmovement and consequently the energy consumption of the railcar. A largenumber of bogies also requires numerous maintenance operations.

There are also a number of high-speed single deck railcars which arenon-articulated and which have distributed motorisation, with differentdistributions of the traction equipment in the carriages, differentlocations of the motor bogies or motor axles, depending on thearchitectures. These railcars comprise a plurality of motorisedcarriages which each rest on two bogies.

This type of motorisation requires a large mass of cables having thepower which is required to connect the energy acquisition device(s) tothe motors, extending through each item of traction equipment, whichcables therefore extend between all the carriages which are equippedwith an acquisition device or an item of equipment of the tractiondrive, or a motor bogie.

There are also single deck or double deck trains with “mixed” connectionand concentrated motorisation. The passenger carriages rest on carrierbogies and are surrounded by two motor cars, at each end of the train,resting on motor bogies. The connections of this train are said to be“mixed” since different types of connections connect the carriages andthe motor cars. The carriages are connected to each other by means of anarticulated connection and the carriages are connected to the motor carsby means of a non-articulated connection.

This architecture has a reduced passenger capacity compared with arailcar having an identical length since the motor cars are notaccessible to passengers.

The efficiency levels of these vehicles are linked to the architecturesthereof: it is possible to cause a high-speed train to travel at lowerspeeds, but at the expense of passenger capacity since the mass oftraction drives cannot be released. It is not possible to cause avehicle to travel at a higher speed than its maximum speed since atraction drive or a motor cannot simply be added. Manufacturers musttherefore design a vehicle which is suitable for every speedrange/passenger capacity.

SUMMARY OF THE INVENTION

The object of the invention is therefore to provide a railcar which doesnot have the disadvantages of the architectures of the prior art.

To this end, the invention proposes a railcar for passenger transportwhich comprises two driving carriages and intermediate carriages,carrier bogies, motor bogies, which comprise at least one motor axle,wherein the carriages are all mutually articulated in pairs, the railcarcomprises three or four traction drives, one traction drive beingarranged in each driving carriage and at least one traction drive beingarranged in a single intermediate carriage, a motor bogie is arrangedbelow at least one of the two ends of the driving carriages, a motorbogie is arranged below at least one of the two ends of the intermediatecarriage which comprises at least one traction drive.

The railcar comprises one or more of the following features, taken inaccordance with any technically possible combination:

-   -   each traction drive drives at least one motor axle of the motor        bogie(s) which is/are arranged below one end or below the two        ends of each carriage in which the traction drive is arranged;    -   the railcar comprises, between the intermediate carriage        comprising at least one traction drive and each of the driving        carriages, at least one intermediate carriage which has no        traction drive;    -   at least one intermediate carriage which has no traction drive        is supported at least at one of the two ends thereof by a        carrier bogie;    -   the carriages are double deck.

The railcar is completely articulated, that is to say that the carriagesare all mutually articulated in pairs. A bogie is arranged in astraddling manner below the two adjacent ends of two adjacent carriages,the free ends of the driving carriages resting on a single bogie.

It comprises three or four traction drives, one traction drive beingarranged in each driving carriage and at least one traction drive (oneor two) being arranged in a single intermediate carriage. For thisreason, this intermediate carriage will be referred to as the motorisedintermediate carriage. The railcar therefore has concentratedmotorisation, the concentration being carried out in three carriages,whether there are three or four traction drives.

A motor bogie is arranged below at least one of the two ends of the twodriving carriages and the motorised intermediate carriage comprising atraction drive. In other words, each carriage which comprises a tractiondrive is supported at the two ends thereof either by a motor bogie and acarrier bogie or by two motor bogies.

The railcar comprises, between the motorised intermediate carriage andeach of the driving carriages, at least one intermediate carriage whichhas no traction drive. Since this intermediate carriage does notcomprise a traction drive, it is referred to as a trailer.

A trailer is supported at least at one of the two ends thereof by meansof a carrier bogie. A trailer is therefore supported at the ends thereofeither by means of a carrier bogie and a motor bogie, or by two carrierbogies.

A railcar according to the invention therefore complies with aregulation for alternating carriages which comprise a traction drive andwhich comprise no traction drive, and a regulation for alternating motorbogies and carrier bogies in order to comply with the maximum axle load.

Indeed, all rail vehicles must comply with the restriction of the axleload, the value of which is set out by the infrastructure or by thestandards relating to the tracks on which these vehicles travel.

The axle load of the railcar according to the invention is kept belowthe maximum admissible load since:

-   -   each driving carriage is supported on a dedicated bogie and a        common bogie with another carriage and the load thereof is        therefore distributed over a larger number of axles than the        intermediate carriages. Consequently, a driving carriage is able        to support a greater mass than the other carriages without        exceeding the maximum axle load. Each driving carriage therefore        receives passengers, the traction drive and all or some of the        auxiliary items of equipment for energy production (electrical        and pneumatic),    -   the trailers which have no traction drives have a lower empty        weight than the driving carriages and the motorised carriage,    -   the intermediate motorised carriage receives passengers and the        items of equipment of at least one traction drive. The motor        bogies at each end of the motorised carriage each support half        of the mass of the motorised intermediate carriage and half of        the mass of the adjacent trailer, since at least one trailer is        interposed between the driving carriage and the motorised        intermediate carriage. Since a trailer is less heavy than the        motorised intermediate carriage, each motor bogie which is        arranged in a straddling manner below one of the ends of the        motorised intermediate carriage and below the end of the        adjacent trailer supports a mean mass which remains lower than        the maximum load per axle.

The balance of the masses on each carrier bogie and motor bogie is alsoobtained by means of optimisation of the distribution of the variousitems of traction equipment or auxiliary equipment of the railcar andthe internal fitting of the carriages which differs depending on thecomfort desired (different type and number of seats depending on theclass of the carriage).

The internal fitting of the motorised intermediate carriage depends inparticular on the mass of the traction drive(s) which are themselvesdependent on the desired performance levels of the railcar(multi-voltage traction, maximum speed, etc.). For example, if the massof the items of traction equipment installed is high, the internalfitting of the motorised intermediate carriage will be reduced in weightand be configured as a buffet car, a carriage which provides services,or which has a reduced passenger capacity compared with the capacity ofthe trailers.

Each traction drive drives at least one motor axle of the motor bogie(s)which is/are arranged below one end or the two ends of the carriages inwhich one or more traction drives are arranged. The railcar may thuscomprise from three to twelve motor axles, depending on whether eachdriving carriage and the motorised intermediate carriage are supportedby one or two motor bogies which themselves comprise one or two motoraxles.

One advantage of an architecture which is completely articulated is thatthe railcar is more stable in the event of derailment. Owing to thearticulated architecture, the resistance to forward movement andtherefore the energy consumption required to drive the vehicle remainslimited compared with a non-articulated railcar of the same length,since there are fewer bogies. The maintenance operations are alsoreduced. Owing to the railcar composition, the vehicle provides a largecapacity since the entire length of the vehicle is used to receivepassengers.

One advantage of the concentration of traction drives in the drivingcarriages and in a single motorised intermediate carriage allows betterprotection from and control of fires by physically separating thetraction drives from each other and by physically separating thetraction drives from the passenger compartments.

The invention and other advantages will be better understood from areading of the following description, given purely by way of example,and with reference to the appended drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1, 3 and 4 are schematic side views of railcars according to theinvention, according to a plurality of embodiments,

FIG. 2 is a table which schematically illustrates the position of themotor axles in accordance with the number of carriages composing therailcar.

Conventionally, the wheels of the motor axles are indicated in black inthe drawings.

DESCRIPTION OF PREFERRED EMBODIMENTS First Embodiment

As illustrated in FIG. 1, a railcar A comprises seven trailers 3 and amotorised intermediate carriage 4 which are arranged between two drivingcarriages 2.

A first driving carriage 2 is located at a first end of the railcar A(from the left-hand side in FIG. 1). It has a free end, where a driver'scabin 9 is located, and rests on a motor bogie 6 which is composed oftwo motor axles 5. A first traction drive 8 is arranged below thepassenger compartment 10 of this first driving carriage 2. At theopposite end thereof, the driving carriage 2 is articulated to a firsttrailer 3. The two ends facing the carriages 2 and 3 rest on a singlemotor bogie 6 which is composed of two motor axles 5.

The first trailer 3 therefore shares, at the first end thereof, a motorbogie 6 with the driving carriage 2 and shares, at the other endthereof, a carrier bogie 7 with the second adjacent trailer 3.

The second trailer 3 is articulated to the first trailer 3 and to thethird trailer 3. The second trailer 3 shares, with each of the first andthird trailer 3, a carrier bogie 7. The third trailer 3 is articulatedto a motorised intermediate carriage 4 which is located in the railcarof this embodiment in fifth position from the left-hand side.

None of the first three trailers 3 receives a traction drive 8.

The motorised intermediate carriage 4 shares, at each of the endsthereof, a motor bogie 6 with the adjacent trailers. Two traction drives8 are arranged below the passenger compartment 10 and supply the motorsof the motor bogies, which each comprise two motor axles, located ateach end of the motorised intermediate carriage 4.

The four subsequent trailers 3 are also articulated and rest on carrierbogies 7, with the exception of the ends of the trailers 3 which arearticulated to the motorised intermediate carriage 4 or to the drivingcarriage 2 which rest on motor bogies 6. The second driving carriage 2is identical to the first.

All the carriages 2, 3, 4 of the railcar A have a passenger compartment10. Each of the carriages 2, 3, 4 communicates with the or each adjacentcarriage by means of a passage 11. Since the vehicle is completelyarticulated, the railcar A of FIG. 1 has eleven bogies, six motorisedbogies 6 and five carrier bogies 7, for a length of approximately 200 m.In this embodiment, all the axles of the motor bogies are motorised. Arailcar of this type may transport at least 550 passengers at acommercial speed of at least 330 km/h.

In each of the driving carriages 2 and motorised intermediate carriage4, the traction drive(s) 8 is/are arranged below the floor of thepassenger compartment 10 in order to retain the length of the passengercompartment 10. FIG. 1 schematically illustrates the location of thetraction drives 8 below the entire length of the passenger compartments10 of the carriages 2 and 4, but depending on the actual spatialrequirement of the various components of the traction drive 8, it mayextend completely or partially below the floor of the passengercompartments 10.

In a variant, the traction drives 8 of the driving carriages 2 may bearranged in intermediate compartments between the driver's cabin 9 andthe passenger compartment 10.

In conventional manner, each of the driving carriages 2 is provided witha pantograph 12 in order to acquire the electrical energy on a catenaryline (not illustrated).

A high-voltage cable 13 distributes the electrical energy acquired byeach pantograph 12 to the traction drive 8 which is located in themotorised intermediate carriage 4. For reasons of clarity in thedrawings, the cables 13 are illustrated at the outer side of thecarriages with dot-dash lines. In practice, these cables extend, forexample, in the roof.

The concentration of the traction drives 8 and the motor bogies 6 over avery limited number of carriages allows the mass of the necessary cablesto be limited, since only high-voltage cables 13 extend between thedriving carriages 2 and the traction drive 8 of the motorisedintermediate carriage 4. These cables have a lower mass than the mass ofthe power cables of the architectures of the railcars of the prior art.The complexity of the cabling is also significantly reduced.

Variants of the First Embodiment

FIG. 2 illustrates, in the form of a table, two possible configurationsof the railcar according to the first embodiment given by way ofexample. Only the driving carriages 2, the motorised carriages 4, thetraction drives 8, the motor bogies 6, the motor axles 5, the carrierbogies 7, the passenger capacity and the possible operating speeds arenumbered.

A railcar which is composed of seven carriages, comprising two drivingcarriages 2, four trailers 3, a motorised intermediate carriage 4 andfour motorised axles 5 requires only three traction drives 8. A singletraction drive 8 is therefore arranged in the motorised intermediatecarriage 4, in contrast to the first embodiment. In this variant, twomotor bogies 6 support the two ends of the motorised carriage 4, buteach has only a single motor axle 5. The space released by the secondtraction drive can be used to install auxiliary equipment or the massreleased can be used to install more seats in the compartment 10 of themotorised intermediate carriage 4. In this same variant, only the bogiesbelow the free ends of the driving carriages 2 are motorised and theyeach comprise two motor axles 5. This variant having seven carriagestherefore comprises four motor bogies 6 but six motor axles 5. Thisrailcar may transport between 350 and 400 passengers (depending on theinternal fitting) and travel at least at 300 km/h.

The second variant of the railcar according to the invention having tencarriages is identical to the variant comprising seven carriages, withthe exception that it comprises three additional trailers. It may havethe same performance levels as the railcar A of the first embodiment byincreasing the power at the axle.

In this manner, the railcar produced according to the invention iscompletely adjustable in terms of passenger capacity and speed since itmay comprise from seven to eleven carriages, three or four tractiondrives 8, from three to twelve motor axles 5 which are distributed overfrom three to six motor bogies 6 and can reach a maximum speed ofbetween 140 and 350 km/h.

This adjustability is achieved by means of the simplification of thetypes of carriages (driving 2, trailer 3 and motorised 4) whilstapplying the regulation for alternating the trailers and the carriageswhich receive a traction drive 8 and the regulation for alternating themotor bogies 6 and carrier bogies 7 in order to comply with the maximumaxle load.

Second Embodiment

As illustrated in FIG. 1, the railcar A comprises only single deckcarriages. In a variant, the driving carriages 2 and the intermediatecarriages 3, 4 are double deck, as illustrated in FIG. 3.

Advantageously, in a railcar B which has double deck carriages, thelower level of a driving carriage 2 and the motorised intermediatecarriage 4 which receives a traction drive 8 is used to accommodate thetraction drive(s) 8, the other level being reserved for passengers.

The passages 11 are placed at the upper level in order to move from onetrailer 3 to another. In contrast, the passages between the drivingcarriages 2 and the adjacent trailers 3 are formed at the lower level. Astairway (not illustrated) which is arranged in the driving carriage 2and in the trailers 3 allows the upper level to be reached from theaccess doors (not illustrated) of the carriages 2, 3, 4.

Third Embodiment

For a short railcar, in the order of from 120 to 160 m, it isadvantageous to reduce the number of motor bogies by removing themotorised intermediate carriage 4 which receives the traction drive(s) 8and removing the associated motor bogies 6.

In this manner, in the variant illustrated in FIG. 4, in which thereferences to the elements which are similar to those of FIG. 1 havebeen retained, a railcar C is distinguished from that of the precedingembodiments in that it comprises only trailers 3 which have no tractiondrives 8. The railcar C therefore has no motorised intermediate carriage4 which receives a traction drive 8.

The railcar C comprises four motorised bogies 6 which are arranged belowthe free ends of the driving carriages 2, and in a straddling mannerbelow the end of a driving carriage 2 and the end of the adjacenttrailer 3. In accordance with the desired power/mass ratio, from four toeight axles could be motorised, each motor bogie 6 having at least onemotor axle 5.

Owing to the removal of the motorised intermediate carriage 4, thepower/mass ratio of a short railcar remains sufficiently high for therailcar to travel at high speed whilst having optimised traction powertaking into consideration the use thereof. This possibility for adaptingthe traction power is not possible on a train, since the motor cars havea traction power which is sized for the maximum number of carriages tobe pulled; if intermediate carriages are removed, the power isneedlessly excessive. The adaptation of the traction power cannot bereadily carried out on a railcar having distributed motorisation sinceremoving a carriage is equivalent to removing an element of the tractiondrive.

1. Railcar for passenger transport comprising: two driving carriages andintermediate carriages, carrier bogies, motor bogies, which comprise atleast one motor axle, wherein: the carriages are all mutuallyarticulated in pairs, the railcar comprises three or four tractiondrives, one traction drive being arranged in each driving carriage andat least one traction drive being arranged in a single intermediatecarriage, a motor bogie is arranged below at least one of the two endsof the driving carriages, a motor bogie is arranged below at least oneof the two ends of the intermediate carriage which comprises at leastone traction drive.
 2. Railcar according to claim 1, wherein eachtraction drive drives at least one motor axle of the motor bogie(s)which is/are arranged below one end or below the two ends of eachcarriage in which the traction drive is arranged.
 3. Railcar accordingto claim 1, wherein it further comprises, between the intermediatecarriage comprising at least one traction drive and each of the drivingcarriages, at least one intermediate carriage which has no tractiondrive.
 4. Railcar according to claim 2, wherein it further comprises,between the intermediate carriage comprising at least one traction driveand each of the driving carriages, at least one intermediate carriagewhich has no traction drive.
 5. Railcar according to claim 1, wherein atleast one intermediate carriage which has no traction drive is supportedat least at one of the two ends thereof by a carrier bogie.
 6. Railcaraccording to claim 2, wherein at least one intermediate carriage whichhas no traction drive is supported at least at one of the two endsthereof by a carrier bogie.
 7. Railcar according to claim 1, wherein thecarriages are double deck.
 8. Railcar according to claim 2, wherein thecarriages are double deck.
 9. Railcar according to claim 3, wherein thecarriages are double deck.
 10. Railcar according to claim 4, wherein thecarriages are double deck.
 11. Railcar according to claim 5, wherein thecarriages are double deck.
 12. Railcar according to claim 6, wherein thecarriages are double deck.